Treatment strategies for concomitant ligament injury in anterior cruciate ligament-injured athletes, a narrative review.

Background and Objective: Multiligament knee injuries (MLKIs), although rare in athletes, can present distinct challenges beyond the high-energy trauma commonly seen in the general population. The combination of anterior cruciate ligament (ACL) injury with other major knee stabilizers creates substantial treatment challenges as most athletes experience pressure to return to top-level sports quickly, while maintaining joint stability over a long career. This narrative review summarizes the epidemiology and biomechanics of common injury patterns, classification systems, surgical decision-making and rehabilitation strategies for managing multiple ligament knee injuries in athletes. Methods: A narrative literature review was conducted using PubMed and MEDLINE databases, targeting English-language studies from 2000 to 2024. Relevant studies were identified through keyword searches including "multiligament knee injury", "ACL reconstruction", "athlete", "return to play", and "concomitant ligament injury". Studies focused on biomechanics, surgical technique, rehabilitation, biologic augmentation, and performance outcomes were included. Key Content and Findings: MLKIs are recognized with an increasing incidence in athletes; however, they are not well studied in the literature outside of traumatic, typically high energy settings. In athletes, management becomes more complex as surgical intervention must be considered in tandem with return-to-play (RTP) necessitating individualized planning. Underlying knee biomechanics can help identify potential risk for specific injury patterns. Surgical reconstruction with autograft in a single staged procedure is preferred due to possible lower risk for re-rupture and potentially quicker return to sport; however, graft selection based on number of ligaments involved and timing of surgery remain points of controversy. Importantly, avoiding tunnel collision during MLKI reconstruction adds a unique challenge and requires thoughtful surgical preoperative planning. Appropriate rehabilitation is critical as well to allow RTP at the same level. Generally, early range of motion with progressive weight bearing is recommended with an additive potential for standardized testing to evaluate for RTP. As MLKI research continues to progress, identifying optimal graft selection, timing of reconstruction, and rehabilitation protocols with a potential role for biologics will improve athletes' successful RTP. Conclusions: MLKIs in athletes present unique challenges that extend beyond those seen in high-energy trauma cases. Coordinating surgical management with RTP goals requires individualized planning and thoughtful rehabilitation. Ongoing research is needed to refine graft selection, surgical timing, and recovery protocols. In this narrative review, we aim to review the literature, highlight treatment gaps and future areas of research, and provide general treatment recommendations to optimize outcomes in this population.